The present invention relates to a cooking vessel, such as a pot or pan, and more particularly to a technique for attaching a handle to the receptacle portion of the cooking vessel.
Present day commercial cookware, such as pots and pans, is generally of all metal construction wherein the receptacle portion of the cooking vessel is made of aluminum and a one-piece steel handle is connected thereto. The handle is connected to the receptacle portion by a plurality of rivets, which extend through openings in the side wall of the receptacle portion and then through openings in the mounting end of the handle. The rivets have rounded heads protruding beyond the inner surface of the receptacle side wall, and the free ends are peened or otherwise expanded beyond the perimeters of the openings in the handle mounting end to rigidly connect the handle to the receptacle.
Although the handle fastening technique described above provides for a very rigid interconnection between the handle and receptacle, the protruding rivet heads within the receptacle interrupt the smooth surface thereof so that food tends to collect on and around them. Such collected food is sometimes difficult to remove thereby presenting a sanitation problem if particular care is not taken when the pan is cleaned.
The interior surfaces of many cooking vessels are provided with a nonstick coating, such as TEFLON. In the conventional technique for applying this nonstick material, the receptacle portion of the vessel is spun while the coating is applied. Due to the difficulties of spinning a pot or pan with the handle already attached, the inner surface of the cooking vessel is coated prior to the attachment of the handle. Thus, the heads of the rivets are not coated with the nonstick material, and food that adheres to it is very difficult to remove. In order to remove this food, it is usually necessary to scrub it with an abrasive material, such as steel wool. The nonstick coating, however, cannot withstand such scouring and it quickly becomes rubbed off in the vicinity of the rivet heads. Then, food tends to stick, not only to the rivet heads, but also to the interior surface of the vessel itself in the vicinity of the rivet heads. Obviously, this reduces the effectiveness and life of the cooking vessel.
One technique for avoiding the necessity of passing rivets through the side wall of the vessel is to attach the rivet directly to the outer surface of the pot or pan, such as by stud welding. This preserves the smooth surface within the pot or pan but presents a substantial problem in attaching the handle to the stud. Because these studs are secured to the outer surface of the vessel by a welding technique, they must be attached before the handle is assembled to them. Most pots and pans are circular in shape so that the surface to which the studs must be attached is curved. Since it is desirable to attach the studs in a radial direction relative to the central axis of the receptacle portion, the studs, when attached, lie along respective radii and are, therefore, divergent with their free ends being spaced further apart than the ends attached to the receptacle. This presents a problem in attaching the handle because, if the spacing between the openings in the handle correspond to the spacing between the bases of the studs, then the handle openings will not align with the free end of the studs to permit the handle to be slipped over them. On the other hand, if the spacing between the openings equals that of the spacing between the free ends of the studs, then the handle cannot be fully inserted over the studs, a condition which is necessary if a rigid connection between the handle and vessel is to be achieved.
Although attaching a handle to a single stud welded to the external surface of the vessel would not present a similar problem in matching openings in the handle, it has been found that a single stud handle fastening technique does not provide the strength and rigidity necessary for commercial cookware. Examples of single stud handle mounting techniques are disclosed in U.S. Pat. Nos. 4,032,032 and 3,648,887.